Transmission



M. S. ARIENS TRANSMISSION Nov. 5, 1940.

Filed Sept. 30, 1936 13 Sheets-Sheet l.

I gvwQ/Wkw Nemdo 5. Avieres NOV. 5, 1940. 5, ARENS 2,220,197

TRANSMISSION Filed Sept. 30, 1936 13 Sheets-Sheet 2 Mamdo 5, Ariens' age M. s. ARIENS TRANSMISS ION .Nov. 5, 1940.

Filed Sept. 30, 1936 13 Sheets-Sheet 3 Nando 5. Ariana Nov. 5, 1940.

M. S. ARIENS TRANSMISSION Filed Sept. 30, 1936 l3 Sheets-Sheet 5 Non/2010 5. Arieras Nov. 5, 1940.

M. s. ARIENS 2,220,197-

TRANSMISSION.

Filed Sept. 30, 1936 13 Sheets-Sheet 6 H1 mvzmon TIcmdo .5. Ariens F 4'1 v Q ATTORNEY Nov. 5, 1940.

M. s. ARIENS 2, 2 97 TRANSMISSION I Filed Sept. 30, 1936 13 Sheets-Sheet 7 INVENTOR Nando 5. Ariana ATTO RN EY NOV. 5, 1940. M s ARlENs 2,220,197

TRANSMISS ION Filed Sept. 30, 1936 13 Sheets-Sheet 8 Nov. 5, 1940. M. s. ARIENS 2,220,197

TRANSMISSION Filed Sept. 30, 1936' 13- Sheets-Sheet 9 1Z5 125 26 INVENTOR Noredo S. Ariews ATTORN EY Nov. 5, 1940. M. s. ARIENS TRANSMISSION Filed Sept. 50, 1936 13 Sheets-Sheet 10 Manolo 2'). Adams mam,

Nov. 5, 1940. M. s. ARIENS 2,

TRANSMISSION Filed Sept. 50, 1936 13 Sheets-Sheet ll W .MNNNN wiwvw v Wk m M. S. ARIENS TRANSMIS S ION Nov. 5, 1940.

Filed Sept. 30, 1936 13 Sheets-Sheet 12 REVQERSE CLUTCH MEMBER 34-ENGAGED NE%AL WITH CLUTCH MEMBER 3\ CLUTCH MEMBERMENQAGED .W\TH GEAR l&

H\G'H-5PEED POWER TAKE-OFF LOW- bPEED POWER TAKE OFF Elma/who e Vim ado 5. Ariens [In I, 6mm

Nov. '5, 1940.

M. s. ARIENS TRANSMISSION Filed Sept. 50, 1936 13 Sheets-Sheet 15 T hndo Elmo/rm 5. Arieres Patented Nov. 5, 1940 UNITED STATES PATENT OFFICE '7 Claims.

This invention relates to transmissions and has particular relation to transmissions of the multispeed or change-speed gear type, by which power is transmitted by means of gear-trains from a power source to the output side at different speeds as selected by an operator.

One object of the present invention is to provide in a transmission an intermediate shaft between the power input and power output shafts and means, such a back gear shaft adapted to be so used in association with the power-input and intermediate shafts, as to drive the intermediate shaft at will at more than one speed with change speed gear mechanism between the intermediate and output shafts to provide a set of speed changes for the output shaft for each speed of the intermediate shaft.

Another object of the invention is to provide a transmission through which may be obtained a number of different speeds in one direction and one or more speeds in reverse direction, but to obtain this result with fewer gears than has been heretofore required.

Another object is to provide a power transmission of small dimensions through which may be obtained extremely large speed reductions.

Another object is to eliminate the necessity for a double reduction between the transmission and the driving axle of automotive and tractor construction. V r 7 Still another object is to provide a transmission in which one or more gears may be utilized for several purposes, as for example, to obtain a direct drive, an indirect drive, or reverse, according to the requirements of the operator.

A still further object is to obtain auxiliary power take-offs, at either high or low speeds or both, from the transmission itself without adding extra gears,-shafts or bearings.

Yet another object is to provide a transmission in which one or more of the gears may be used to perform the function of an oil-thrower whenever the power-input shaft is in operation in neutral or in gear.

Another object is to provide a transmission in which the power-input shaft is well above the center of the rear axle, which makes possible a greater clearance between the bottom of the englue and the ground, and permits the propeller shaft to be located well below the center line of the engine, thereby eliminating the necessity of having either a high floor line orv a raised casing above the floor line of automotive vehicles or the like.

Another object is to provide a simple gear shifting mechanism which will operate easily and effectively in connection with a gear transmission having a large number of speed changes.

Other objects will be readily seen from the following brief description of the mechanismin connection with the accompanying drawings thereof.

Of the accompanying drawings:

Figure 1 is a vertical cross-section through a form of the mechanism embodying the invention, taken substantially on the line |-i of Figure 3. Fi e 2 is a horizontal cross-section taken on the line 22 of Figure 1.

Figure 3 is a vertical cross-section taken on the line 3-3 of Figure 1.

Figures 4 and 5 are fragmentary cross-sectional views of a portion of the mechanism shown in Figure 2, illustrating various steps in the operation thereof.

Figure 6 is a cross-section taken on the line 6-6 of Figure 2.

Figure 7 is a horizontal cross-section of the transmission shown in Figures 1 to 6 with a few changes in the construction thereof.

Figure 8 is a cross-section taken substantially on the line 88 of Figure 7.

Figure 9 is a vertical cross-section similar to Figure 1, illustrating another embodiment of the invention, and taken substantially on the line 8-8 of Figure 11.

Figure 10 is a horizontal cross-section taken on the line lO-IO of Figure 9.

Figure 11 is a vertical cross-section taken on the line I l--! l-of Figure 9.

Figures 12 and 13 are fragmentary cross-sectional views of a portion of the mechanism shown in Figure 9,.illustrating various steps in the operation thereof.

Figure 14 is a vertical cross-section similar to Figure 1, illustrating still another embodiment of the invention, taken substantially on the line ll-M of Figure 15.

Figure 15 is a horizontal cross-section taken on the line I5l 5 of Figure 14.

Figure 16 is a fragmentary rear view, on a reduced scale, of a differential housing of a vehicle, illustrating the use of an auxiliary power take-oil in connection with Figures 14 and 15.

Figure 17 is a fragmentary top view of a preferred form of gear-shift mechanism illustrated in connection with a form of transmission substantially the same as that shown in Figures 1, 2 and 3.

Figure 18 is a diagrammatic view of the various shifts obtainable with the mechanism shown in Figure 17.

Figure 19 is a vertical cross-section taken on the line l9-l9 of Figure 17.

Referring to Figures 1 to '1 inclusively, of the drawings, I0 is a transmission housing which may be integral with a differential housing ll of any automotive vehicle or tractor, or it may be secured in any suitable manner to power means where speed changes are desired. Rotatably journaled in a suitable bearing l2, at the top of the housing in is a power-input shaft l3 which may be coupled or clutched to a power source or en gine (not shown).

An intermediate shaft l4, on the same axis with the power-input shaft I3, is journaled at one end in a suitable bearing l5 within a counterbore It in the end of the input shaft l3, and is journaled at its other end in a bearing l1 mounted in the casing I0. Secured to the shaft l4 intermediate the ends thereof is a gear 18, said gear being prevented from lateral movement by means of circular keys l9, l9 and from relative rotation by teeth I4 on said shaft serving as splines. Slidably but non-rotatably mounted on the intermediate shaft I4 is a combined gear and clutch member 2|, said member being provided with internal clutch teeth 22 engaged with the teeth or splines I4 on the intermediate shaft and selectively engageable with external teeth on a gear member 23 which latter is fixed on the end of the input shaft whereby gear and clutch member 2i may function as a clutch connecting the input shaft is with the intermediate shaft l4.

Located at a suitable distance below the intermediate shaft i4 is a power-output shaft 24, journaled in bearings 25 and 26 in the housing l0 and a bearing 21 in a bevel-pinion housing 23, which latter may be integral with the housing 'may be ll. Secured to the shaft 24 at the endadjacent the bevel-pinion housing '23 is a' supporting spider 23, having an annular bearing surface 33 about which a combined gear and clutch member 3| may be freely rotatable. The gear and "clutch member 3| may be provided'with' external teeth 32 engageable with the teeth H on the shaft I4, which may provide a' suitable gear on said shaft, and may also be provided with internal teeth 33 with which a gear or clutch member 34, shiftably but non-rotatably mounted on the shaft 24, may be engageable to provide a clutch. Lateral displacement of the gear and clutch member 3i prevented by means of an annular key 25 and an annular flange 23" on the supporting spider 23. The gear and utch member 3| may be utilized as an oilhrower at all times when the intermediate shaft is driven.

' Referring to Figures 2 and 3, adjacent the intermediate shaft I4, is aback-gear shaft 35, suitably journaledin bearings 33, 33 in transmission housing ll. Gears 3! and 33, which may be integral with each other, are keyed to the shaft 35 in such a manner that said gear 33 may be in constant mesh with'the gear 23 on the power-input shaft l3. The back-gear shaft 35 may be extended at 33 to provide a constant source of power take-off for any desired purpose, as for example for rear-end pupling drives to other machinery such as binders or similar units.v

The transmission may be connected to a conventional form of'diflerential by securing on shaft 24 a bevel pinion 40 which may mesh with a bevel gear such as 4| attached to the differential.

Any suitable gear-shifting means may be used, but Figures 1 to 6, inclusively, illustrate one type of mechanism which may be adapted for use with a transmission of this type. A pair of shifter rails 43 and 44 are shown slidably mounted in a shifter-rail support 42 integral with the transmission housing III. The shifter rail 43 may be provided, at the end within the transmission housing, with a shifter fork or yoke 45, adapted to engage the gear or clutch member 34 as will be understood to shift the latter on the power-output shaft 24. The shifter rail 44 is similarly provided with a shifter "engage the gear member 2| to shift the latter on the inter-mediate shaft l4 or to shift it into clutching engagement with the gear 23.

Slidably journaled in a support 41 at the top of the differential housing is a shifter crank 43, comprising a handle 49 extending upwardly, a horizontal portion 53, and a downwardly extending crank arm 5|. The crank arm 5| is provided at its lower end with suitably shaped extension 52 adapted to be shiftably engaged with a slot 53 in the shifter rail 44 in the neutral position shown in Figures 1 and 2, and with slot 53 on shifter rail 44 and also slots 54, 55, and 55 on the shifter rail 43 for the various shifts as desired by the operator, which will subsequently be described. The shifter rail support 42 may be provided with wall l0 adjacent the differential housing II, to permit the crank arm H to swing freely.

A suitable interlock is provided to eliminate the possibility of both shifter rails being shifted at the same time. This interlock comprises a conventional ball 53 imprisoned in an opening 53 in the wall between bores 6i and 82 in which the shifter rails are slidable. Notches 63, 84 and 55 in a recess 33 in the shifter rail 44, and I1, 88, 89 and III in a recess II in the shifter rail 43, may be provided as is best shown in Figures 2, 4, 5 and 6. These notches are so spaced that when .one or other of the shifter rails is moved to any one of the predetermined positions to obtain a desired speed, the ball 53 slips into a notch in the opposite shifter rail as said ball is forced over by contact with the surface of the recess of the rail then being shifted.- The ball thus forced into a notch holds one shifter rail in a fixed position while the other shifter rail is being moved. In the description of a complete cycle of operation it will be assumed that the input shaft l3, and the back-gear shaft 35 through gears 23 and 33, are being constantly driven. The gear. -31, being integral with the gear 33, will then also be constantly driven.

Figure 1, 2, and 3, in their full line positions, show the transmission in neutral. In this con dition none of the gears are in driving connec-' tion to'the power-output shaft and consequently no power is transmitted thereto. There is, however, a driving connection to the back-gear shaft 35. j

The arrangement of the various gears for reverse shift is best shown in chain-dotted lines -in Figures -2 and 3. Starting with all the'gears otherwise arranged as for neutral, the shifter crank 43 is moved from the full line position to the chaindotted position, as shown in Figure 3,

so that the extension 52 of the crank arm 5| slides out of engagement with the slot 53 on the shifter rail 44, into engagement with the slot 55 in the shifter rail 43 (see Figure 2). With the extension 52 thus engaged the crank arm 5| may be swung to the left, as viewed in Figures 1 and 2,

until the gear 34, through the shifter fork 45, is

moved into engagement with the gear 31 to drive the power-output shaft 24 in reverse direction.

'After this operation has been accomplished the shifter rail 43 brought back to the full fork or yoke 45 adapted to line position shown in Figure 2, with the slot 55 opposite the slot 53, and the extension 52 again engaged with'the slot 53.

First, or low speed, is obtained by engaging extension 52 with the slot 53 at the neutral position of both sh i fter rails and sliding the shifter rail 44 to the right until the slot 53 is opposite the slot 56. This brings the gear and clutch member 2| into engagement with the gear 31, through the shifter fork 46. Now, by sliding the extension 52 into the slot 56, the shifter rail 43 may be moved to the right to bring the clutch member 34 into clutching engagement with the gear and clutch member 3|, as is best shown in Figure 4. This arrangement gives a. driving connection between the intermediate shaft I4 and the power-output shaft 24 for the slowest speed of the intermediate shaft.

Second speed is obtained by moving the shifter rail 43 from the full line position to the chaindotted position shown in Figure 4, the ball 58 remaining in looking engagement with the shifter rail 44,-until the gear 34 engages with the gear I8 on intermediate shaft I4 to drive the power output shaft at another speed for the slowest speed of the intermediate shaft.

When third speed is required the driving connection between the power-input shaft I3 and the intermediate shaft I4 must first be changed from indirect to direct. This is accomplished by shifting the shifter rail 43 from its position shown in full lines in Figure 4 to its neutral position which will bring the slot 56-on rail 43 to a point opposite the slot 53 on rail 44, and sliding the extension 52 into the slot 53. This step will disengage the clutchmember 34 from the gear and clutch member 3|. With the extension 52 thus engaged the shifter rail 44 may be moved to the left, disengaging the clutch member 2| from the gear 31- and clutchingly engaging it with the gear 23 on the power-input shaft, thereby driving the intermediate shaft I4 at the same speed as the powerinput shaft. This last step will bring the slot 53 in rail 44 opposite the slot 54 on the shifter rail 43. Sliding the extension 52 into the slot 54, the shifter rail 43 may now be moved to the right to engage the clutch member 34 with the gear and clutch member 3|, thereby obtaining third speed. The final arrangement of the parts for third speed is best shown in the full line position of Figure 5.

Fourth speed may be obtained with the same direct connection between the power-input shaft I3 and the intermediate shaft I4. With the extension 52 still engaged with the slot 54, the shifter rail 43 may be moved to the left, disengaging the clutch member 34 from the gear and clutch member 3| and engaging it with the fixed gear I8 on the intermediate shaft I4, as indicated by the chain-dotted position of the shifter rail 43 in Figure 5.

The neutral position of the gears may again be obtained by moving the shifter rail 43 to the right until the slot 54 is opposite the slot 53, sliding the extension 52 into slot 53, and moving the shifter rail 44 to the right until the extension is opposite the slot 55, thereby bringing all the parts back to the positions shown in full lines in Figure 2.

Figures '7 and 8 illustrate the use of a conventional ball and socket type of gear-shift lever with the same general arrangement of gears as is shown in Figures 1 to 6. The gear-shift lever 15,

which may have a spherical portion 16 integral therewith, is swivelly mounted in a socket member 11 at the top of the transmission housing III.

A suitable dirt coverand grease retainer 13 of flexible material may be provided. The lower end of the lever 15 may be provided with a suitably shaped extension 15 shiftable into engagement with a slot or recess 19 formed on a block 88 fixed on a shifter rail 8|, or shiftable into engagement with similar slots or recesses 82, 83. and 84 formed on a block fixed on a shifter rail 86, said shifter rails being slidably supported in the end walls III and I 0" of the transmission housing. A suitable interlock, indicated at 81, may be provided to prevent more than one shifter rail from being moved at a time. The shifts for the various speeds are precisely the same as has already been described in connection with Figures 1 to 6.

In construction disclosed inFlgure 7 the powerinput shaft has been extended all the way through the transmission housing, said shaft being journaled-in suitable bearings 88, 83 in the walls III and I 0' respectively. Journaled on the shaft I3, intermediate the gear and clutch member 23 thereon and the wall III of the transmission housing may bean intermediate shaft I4". The shaft I4 functions the same as the shaft I4 in Figure 1, the purpose of the extension therethrough being to provide a constant source of high speed power take-off in addition to the power take-oil provided through the back-gear shaft.

Figures 9 to 13 of the drawings disclose another embodiment of the invention. The numeral H8 ,is a transmission housing similar to that disclosed in Figure 1. Rotatably iournaled in a suitable bearing H2 at the top of the housing H0, is a power-input shaft 3 which may be coupled or clutched to a power source or engine (not shown).

An intermediate shaft II4, on the same axis with the power-input shaft H3, is journaled at one end in a suitable bearing H5 within a counterbore I I6 in the end of the input shaft II 3, and is journaled at its other end in a bearing I" mounted in the casing IIU. Secured to the shaft II4 adjacent the right-hand end thereof is a gear 'I I8, said gear being prevented from lateral movement by means of a circular key' H8 and from rotational movement by teeth II4' on said shaft serving as splines. The gear 8, and a circular key I20 secured to an extension of the intermediate shaft II4, prevent lateral movement of said shaft II 4. Slidably mounted on the intermediate shaft II 4 so as to rotate in driving engagement therewith is a combined gear and clutch'member I2I, which may be used for a series of operations presently to be described. Said combined gear and clutch member has clutch teeth IZI, adapted to engage with a clutch member H3 on the end of the input shaft H3, and also has external gear teeth I2 I Located at a suitable distance below the intermediate shaft 4 is a power output shaft I 22, journaled in bearings I23 and I24 in a bevel gear housing III. Secured to the shaft I22 at the end adjacent the shaft 4 is a driving spider I26, which is essentially a cylinder having a plurality of external splines I21. The splines I21 are interrupted at a point adjacent the left-hand end of the cylinder to define a continuous cylindrical surface I28.

- Slidably mounted on the spider I26 so as to rotate therewith are relatively large gears I28 and I30, the interior bores of which are provided with spline-ways |3I and I32 to cooperate with the splines I21. The arrangement is such that the gear I36 may be moved out of engagement with the splines I21 into the space I28 defined by interruptions in said splines, for the purpose of utilizing said gear as an oil-thrower at all times when the gear and clutch member I2I is being driven, either directly through the input shaft I I3, or indirectly through a back-gear train presently to be described.

Referring to Figures and 11, adjacenttho intermediate shaft III, is a back-gear shaft Ill. suitably journaled in bearings I30, I35 in the transmission housing IIO. Gears I30 and I31, which may be integral with each other, are keyed to the shaft I34 in such a manner that said gear I31 may be in constant mesh with a gear I I3 on the power input shaft III. The back-gear shaft I34 may be extended rearwardly above the differential at I34 to provide a constant source of power take-01f.

Integral with the power-output shaft I22, at a point intermediate the bearings I23 and I24, there may be a bevel-gear I23 adapted to mesh with a bevel-gear I3! of a type commonly used in differentials in the automotive industry.

A suitable gear-shifting mechanism (not shown) may be provided to slide each of the gears I29 and I30 and the gear and clutch member I2I along their respective axes in any direction, either independently or in various combinations with each other. Thus it is possible to drive I the intermediate shaft Ill at the same angular velocity as the power-input shaft I I3, or said intermediate shaft may be driven at a different speed indirectly, through the back-gear train.

With these two speeds of the intermediate shaft Ill, and the various combinations of gear connections that may be made between the gears H3 and I2I" on the shaft III, and the gears I29 and I30 on the spider I20, there may be obtained at least one speed in reverse and at least four speeds forward.

In the description of a complete cycle of operation it will be assumed that the input shaft H3 and the back-gear shaft I34, through gears H3" and I31, are being constantly driven.

Figures 9, 10, and 11, in their full line positions, show the transmission in neutral. The driven gear II3 on the input-power shaft III meshes with a gearIiII on the back-sear shaft I34. Integral with the gear I31 theremay be a smaller gear I36 adapted to mesh with the gear I2I on the intermediate shaft Ill. This arrangement drives the shaft 1 ll at a lesser rotary speed than the input shaft Ill, as is permitted by the bearing connection between said shaft III and said shaft H3. The gear I21 in turn drives the large gear I30, whichT however, being out of engagement with the splines I21, is free to revolve on the bearing surface I28 in the space I around the spider cylinder I25. This rotation of the gear I utilizes it as an oil-thrower, while the spider I26 and its connecting parts, including the gears I30 and I30, remain at rest.

The arrangement of the various gears for the reverse shift is best shown in chain-dotted lines in Figures 9 and 10. The clutch member I2I is in driving connection with the input shaft I II for the double purpose of driving the oil-throwing gear I30 and at the same time holding it out of the way of the gear I20. The latter gear is shifted tothe left to mesh with the back-gear Iii-and thereby drive the spider I20 in the re- 7 verse direction.

First or low speed may be obtained, with gear I2 I engaged with gear I and driving shaft by smit s the large gear I20 to the full line.

gear Ill through splined shaft I22 and the bevel- I gear I30. It will readily be seen that the slower speed of the spider I26 does not affect the rotation of the gear I30, since the latter is freely rotatable about said spider when the gear I30 is within the space I23.

Second speed may be obtained by shifting the gears I20 and I30 from the positions shown in full lines in Figure 12 to the positions shown in chaindotted lines in Figure 12. In this condition the gear I30 may be moved into driving mesh with the gear I2I and splined connection with the spider I23.

When third speed is required the driving connection between the input shaft H3 and the intermediate shaft Ill must first be changed'from indirect to direct. This is accomplished by, shifting the gear and clutch member I2I to the left,

as shown in Figure 13, until its clutch member I2I is in engagement with the clutch member 3* on the input shaft II3. At the same time the gear I29 may be shifted to the right to mesh with the gear II8 as shown in full lines in Figure 13. This arrangement of the gears drives spider I20, and its related parts, in a manner similar to that described for first speed, except that the intermediate shaft by being driven at a greater angular velocity, drives the spider and its related parts at greater angular velocity more nearly approaching engine speed. 1

Fourth speed may be obtained with the same direct connnection from the shaft II3 to the intermediate shaft, but with the gear I20 shifted to left out of engagement with gear H8, and the gear I30 shifted to the left to fully mesh the gear I2I as shown in chain-dotted lines, Figure 13. This brings the gear I30 to drive the spider I20 through its splined connection therewith. With the embodiment of the invention illustrated in Figures 14, 15, and 16 a very desirable result, that of providing at least four speeds forward and four in reverse, may be accomplished without the use of any more gears than were required in the previous embodiments of this invention. Such a result is desirable for the reason that there are numerous vehicles or mechanisms wherein a selection of reverse speeds may be useful, as for example gasoline rail cars, tractors, etc.

Referring to Figures 14, 15, and 16, the numeral I00 designates a transmission housing of suitable construction for any desired purpose. Rotatably journaled' in suitable .bearings I5I, I5I at the top of the housing IIO, and extending therethrough, is a power-input shaft I52 which may be coupled or clutched to a power source or engine (not shown). Slidably splined adjacent one end of said shaftli2 is a combined gear and clutch member I53. I

Coaxially iournaled on bearings I54 about shaft I02, adjacent one end thereof, is an intermediate shaft I55. Integral with the shaft I55. a t the o end adjacent the gear and clutch" member I 53 and engageable therewith there may be a clutchmember I00. At the same end of said. shaft and integral therewith there .may

thereof, there may be a gear III.

be-a gear 151."

Aisointegral with the shaft I, at'the other end Suitably positioned below the power-input shaft I52 and the intermediate shaft I55 is a poweroutput shaft I56, journaled in bearings I in the transmission housing I55. The shaft I55 may extend through both ends of the housing to provide twin drives, as for example to the front and rear ends of a vehicle. Slidably splined on the output shaft I59 are gears I6I and I62, engageable with the gears I56 and I58 respectively on the intermediate shaft and with gears on a back-gear shaft presently to be described.

Adjacent the power-input shaft is a shaft I63 journaled in bearings I63, I63 in the transmission housing I50. Keyed or splined to said shaft I63 there may be a back-gear shaft I64 having integral therewith gears I65, I66 and I61, the gear I66 being in constant mesh with the gear I56 on the intermediate shaft I55. The shaft I63 may be extended as at I66 rearwardly above the differential I69, through the differential housing I16 as shown inFigure 16, to provide a constant source of two speed auxiliary power take-off.-

For the purpose of describing this embodiment of the invention it will be assumed as before that the power-input shaft I52 is constantly driven. The full-line positions in Figures 14 and 15 show all gears in neutral. The low speed of the intermediate shaft I55 is obtained when the gear and clutch member I53 is in the chain-dotted position shown in Figure 14, and the high speed is obtained when said member I53 is in the chaindotted position shown in Figure 15.

First speed forward may be obtained by first shifting gear and clutch member I53 to theleft into driving engagement with the gear I on the-back-gear shaft I64, and then shifting gear I62 on the power-output shaft I56 to the left into engagement with gear I61 on said back-gear shaft.

Second forward speed may be obtained with the same driving connection between gear and clutch member I53 and gear I65, but by disengaging the gears I 62 and I6! and shifting gear I6I on the power-output shaft into engagement with the gear I65 on the back-gear shaft I64.

Third speed forward may be obtained by first disengaging gears I6I and I65, shifting the gear and clutch member I53 out of engagement with the gear I65 on the back-gear shaft I64 and into ;clutching engagement with the intermediate shaft I55, by means of clutch member I56, to drive the back-gear shaft I63 at a higher rate of speed, and then shifting gear I62 into engagement with the gear I61 on the back-gear shaft Fourth speed forward may be obtained, with the same driving connection i'rom the power-input shaft to the intermediate shaft I55 as for third speed, but by disengaging-the gears I62 and I61 and shifting the gear I6I on the poweroutput shaft I59 into driving engagement with the gear I65 on the back-gear shaft I64.

The various speeds in reverse may be accomplished in much the same manner as werethe forward speeds, except that the gears I6I and I62 on the power-output shaft are engaged directly with the gears I51 and I56, respectively, on the intermediate shaft I 55, rather than engaging with the gears I61 and I66 on the back-gear shaft I64. a

The first speed in reverse may be obtained by engaging the gear andclutch member I53 on the power-input shaft with gear I65 on the backgear shaft, to drive the intermediate shaft at its low speed through the gears I66 and I61, and

then shifting the gear I62 on the power-output shaft to the right into driving engagement with the gear I56 on the intermediate shaft.

Second reverse speed may be obtained, with the intermediate shaft still engaged for low speed thereof, by disengaging the gears I 62 and I56 and shifting the gear I6I on the power-output shaft into driving engagement with the gear I51 on the intermediate shaft I55.

Third reverse speed may be obtained by shifting the gear and clutch member I53 out of engagement with the gear I65 and into clutching engagement with the intermediate shaft I55, by means of clutch member I56, said intermediate shaft at its high-speed, then disengaging the gears I6I and I51, and shifting the gear I62 on the power-output shaft into driving engagement with the gear I56 on the intermediate shaft I55.

Fourth reverse speed may be obtained with the same clutching engagement to the intermediate shaft I55 as for third reverse speed, but by disengaging the gea'rs I62 and I56 and then shifting the gear I6I on the power-output shaft into driving engagement with the gear I51 on the intermediate shaft I55.

This four speed forward and reverse transmission is adapted to be used with any conventional bevel geared axle wherein the direction of drive may be determined by the position of the driven bevel gear I'll, shown in Figure 16. That is, the direction is determined by whether said bevel gear is positioned on the right or left side of the driving bevel pin I12, said bevel gear I1I being in driving engagement with a bevel pinion I13 on i the power-output shaft I 59. It should be understood therefore that the forward speeds described above can be changed to reverse speeds and the reverse speeds to forward speeds by changing the positions of the final bevel gears.

It is very desirable to provide an auxiliary power take-off shaft which can be operated independently of the axle drive, for coupling connection to auxiliary machinery such .as combine harvesters, corn binders, etc. Furthermore, it is also desirable that such power take-oil shaft be driven at more than one speed so that variations in engine speed can be compensated for. The arrangement shown in Figures 14, 15 and 16 provides a new and simplified two speed power take-off construction, the power take-off shaft being driven at one speed when the combined gear and clutch member I53 on the power-input shaft is in driving engagement with the gear I65 on the backgear shaft, and at 'a higher rate of speed when said gear and clutch member I53 is in clutching engagement with the intermediate shaft I55.

Figures 17, 18 and 19 illustrate another type of gear-shifting mechanism which may be adapted for use in connection with the transmission first described, although it may also be adapted for use with other types of transmissions having a large number of speed changes. The arrangement of-the gears, shafts, etc., in Figures 1'7 and 19 is substantially the same as that shown in Figures 1, 2-and 3 except that the power-output shaft 24 has been set back in order to provide clearance between the bevel-gear M and anextension I4 on the intermediate power transmission shaft I4. This extension Il may extend rearwardly above the differential, through the differential housing (not shown), to provide a source of two-speed power take-off, the speeds thereof being selective, when the transmission is in neutral, and non-selective when the transmission is otherwise in use.

Referring to Figures 17 and 19, removably mounted at the top of the transmission housing I8, as by screws I88, is a shifter-cradle I8I having channels I82 and I88 therein, said channels being separated by a rib I84. Slidably mounted in the channels I82 and I88 are shifter-rails I85- condition, are slots I8I, I82 and I88 respectively.

The slot I82 may be slightly raised to identify it during the shifting operations, as it is only used for changing the power take-off speeds in the neutral condition of the transmission. Fixed on the outside wall of the channel I82 is a member I84 from which may be forced a spring-pressed ball I85 into notches I88, I81, I88 and I88, respectively, in the shifter-rail I85 to hold the lat-' ter in its various shift positions. A similar member 288, fixed on the outside wall of the channel I88, is adaptedto press a ball 28I into notches 282, 288 and 284, respectively, in the shifter-rail I88 to determine the various shift positions thereof. Extending downwardly from the shifter-rail I85, through an opening 285 in the channel I82, is a shifter-fork 288 adapted to engage the gear and clutch member 84. The shifter-rail I88 is similarly provided with a shifter-fork 281, extending downwardly, through an opening 288 in the channel I88, to engage with the gear and clutch member 2|. Pivotally mounted in the transmission housing cover 288 is a downwardly extending shifter-lever 2I8, having a spring-pressed extension 2 at the lower end thereof, said extension being adapted to be used and engaged with the various notches in notch I81, sliding the rail the shifter-rails.

From the neutral position, as is best shown in Figures 17 and 18, first and third speeds are obtained by first engaging extension 2 in the I85 to the right'to engage gear and clutch member 84 with gear and clutch member 8|, sliding the extension 2 through slot I? to engage the notch I88, then sliding the rai I88 to the right to engage gear and clutch member 2I with gear 81 for first speed, or to the left to engage it with gear and clutch member 28 for third speed. Second and fourth speeds are similarly obtained. Starting from neutral again the rail I85 is moved to the left until notch I81 is opposite notch I88, in which position the gear and clutch member 84 will be engaged with gear I8, then the extension is slid through slot I8I to engage with the notch I88 in the rail I88 to slide the latter to the right ot engage gear and clutch member 2I with gear 81-for second speed, or to the left to engage with gear and clutch member 28 for fourth speed. Reverse speed may be obtained by leaving the rail I88 in its neutral position and sliding the rail I85 to the extreme left to engage the gear 84 with gear 81, all other shiftable gears being in neutral position. The power take-off from the extension I14 on the intermediate shaft I4 may of course be utilized at any time when the intermediate shaft is being driven with the restriction that the speed thereof is determined by the speed of said intermediate shaft being transmitted to the power-output shaft at the time. However, when the t ansmission is otherwise in neutral at least two selective speeds of the power take-of! may be obtained by sliding extension 2 over slot I82 to engage notch I88, then sliding the rail I88 either to the right to engage gear and clutch member 2| with gear 81 to obtain the low speed power take-off, or to the left to engage said member 2| with gear and clutch member 28 to obtain the high speed power take-off.

From this brief description of the construction and operation of the invention it is readily seen that, with the addition of one or more gears, many more speed changes may be accomplished without materially increasing the bulk of the mechanism. The embodiments of the invention herein described have all been designed to procure an under-drive, but with a few slight changes in the pitch diameters of the gears an over-drive may be obtained. The invention, in general, provides a transmission with a wide range of speed changes in both forward and reverse, and in a smaller space than has heretofore been accomplished with the conventional types of transmissions.

Modification may be resorted to without departing from the spirit of the invention or the scope of the appended claims, which are not limited wholly to the specific construction shown or to the exact procedure described.

What is claimed is:

1. In a change-speed gear transmission, a power-input shaft, an intermediate power-transmission shaft, a back-gear shaft in driving engagement with said intermediate shaft, means whereby said power-input shaft may drive said intermediate shaft either directly or indirectly through said back-gear shaft to obtain more than one speed of the intermediate shaft, 9.

. power-output shaft, gears on said intermediate shaft, gears on said back-gear shaft, shiftable gears on the power-output shaft engageable with said gears on the back-gear shaft to drive the output shaft at a different series of speeds in one direction for every speed of the intermediate shaft said shiftable gears on the output shaft being also engageable with said gears on the intermediate shaft to drive the output shaft at a different series of speeds in the other direction for every speed of the intermediate shaft.

2. In a change-speed gear transmission, a power-input shaft having a combined gear, and clutch member slidable thereon, an intermediate power-transmission shaft having a clutch member and one or more gears thereon, a backgear shaft having one or more gears thereon and adapted to be in driving engagement with said intermediate shaft, a power-output shaft having shiftable gears thereon, said gear and clutch member on the input shaft being adapted to be engaged with at least one ge'ar onthe back-gear shaft or clutched to said intermediate shaft, whereby both the back-gear shaft and the intermediate shaft can be selectively driven at more than one speed, said gears on said output shaft being selectively engageable with said gears on the back-gear shaft to obtain a different series of speeds in one direction for every speed of the back-gear shaft, or with said gears on the intermediate shaft to obtain a different series of speeds in the other direction for every speed of said intermediate shaft.

3. In a change-speed gear transmission, a .power-input'shaft having a combined gear and clutch member selectively shiftable thereon, an

intermediate power-transmission shaft coaxially journaled about said power-input shaft, a clutch member on said intermediate shaft, a back-gear shaft having a gear thereon engaging with a gear on the intermediate shaft, a second gear on the back-gear shaft, said gear and clutch member being selectively engageable with said second gear on the back-gear shaft to drive the intermediate shaft at one speed or .engageable with said clutch member on the intermediate shaft to drive the latter at a second speed, a third gear on the back-gear shaft, a second gear on the intermediate shaft, a power-output shaft, a gear on the power-output shaft selectively shiftable into engagement with said third named gear on the back-gear shaft or with said second gear on the intermediate shaft to obtain one speed in one direction and one in the other direction for every speed of the intermediate shaft, and a second gear on the output shaft selectively shiftable into engagement with said second named gear on the back-gear shaft or with said first-named gear on the intermediate shaft to obtain one speed in one direction and one in the other direction for every speed of the intermediate shaft.

4. In a change-speed gear transmission, a power-input shaft, an intermediate power-transmission shaft, a back-gear shaft adapted to be in.

driving engagement with said intermediate shaft, a power-output shaft, gears on all said shafts, means for selectively engaging said intermediate shaft with said input shaft or engaging a gear 'on the input shaft with a gear on the back-gear shaft to drive said intermediate shaft at different speeds and thereby drive the back-gear shaft at different speeds, gears on said output shaft adapted to be selectively used and engaged with gears on said intermediate shaft to obtain a different series of output-shaft speeds for each intermediate shaft speed, and said gears on the said output shaft being adapted to be selectively used and engaged with said gears on the back-gear shaft to obtain a. different series of output-shaft speeds for each back-gear shaft speed.

5. In a change-speed gear transmission, a power-input shaft, an intermediate power-transmission shaft, a back-gear shaft adapted to be an auxiliary drive, means whereby said power-input shaft may drive said intermediate shaft and said back-gear shaft at more than one speed, a poweroutput shaft, gears on said intermediate shaft,

, gears on said back-gear shaft, shiftable gears on the power-output shaft engageable with said gears on the back-gear shaft to drive the output shaft at a different series of speeds forevery speed of the back-gear shaft said shiftable gears on the output shaft being also engageable with said gears on the intermediate shaft to drive the output shaft in opposite rotation at a different series of speeds for every speed of the intermediate shaft.

6. In a change-speed gear transmission, a gear mounted therein to be independently rotated at different speeds, a power input shaft on one center, means for connecting said gear to said power input shaft to be driven at one speed, means comprising a shaft and gearing on a second center for indirectly driving said gear from said input shaft at another speed, and a power output shaft on a third center and having thereon a gear for meshing withsaid independently rotated gear at either speed thereof, the firstnamed gear meshing with gearing on said second shaft and also meshing with gearing on said output shaft and adapted to drive the output shaft and be simultaneously driven by the second shaft.

7. A change speed gear mechanism comprising an input shaft on one center, a second shaft and gearing on a second center and an output shaft and gearing on a third center, gearing on said input shaft for meshing with the gearing on said second shaft to drive the latter at a plurality of different speeds, said second shaft having a power take-off portion whereby said second shaft may be adapted to drive an external power-operated device as desired at a plurality of different speeds, said input shaft gearing and said second shaft gearing being adapted to mesh with gearing on said output shaft to drive said output shaft at a plurality of different speeds in both directions of rotation. 

